Select all of the names of this polygon.

Find the indicated probability. The weekly salaries of teachers in one state are normally distributed with a mean of $490 and a

Alecsey [184]

Given Information:

Mean weekly salary = μ = $490

Standard deviation of weekly salary = σ = $45

Required Information:

P(X > $525) = ?

Answer:

P(X > $525) = 21.77%

Step-by-step explanation:

We want to find out the probability that a randomly selected teacher earns more than $525 a week.

$P(X > 525) = 1 - P(X < 525)\\\\P(X > 525) = 1 - P(Z < \frac{x - \mu}{\sigma} )\\\\P(X > 525) = 1 - P(Z < \frac{525 - 490}{45} )\\\\P(X > 525) = 1 - P(Z < \frac{35}{45} )\\\\P(X > 525) = 1 - P(Z < 0.78)\\\\$

The z-score corresponding to 0.78 from the z-table is 0.7823

$P(X > 525) = 1 - 0.7823\\\\P(X > 525) = 0.2177\\\\P(X > 525) = 21.77 \%$

Therefore, there is 21.77% probability that a randomly selected teacher earns more than $525 a week.

How to use z-table?

Step 1:

In the z-table, find the two-digit number on the left side corresponding to your z-score. (e.g 0.7, 2.2, 1.5 etc.)

Step 2:

Then look up at the top of z-table to find the remaining decimal point in the range of 0.00 to 0.09. (e.g. if you are looking for 0.78 then go for 0.08 column)

Step 3:

Finally, find the corresponding probability from the z-table at the intersection of step 1 and step 2.

3 0

2 years ago

Of the following points, name all that lie on the same horizontal line?

ArbitrLikvidat [17]

I just graphed all 4 and didn’t see where any are on the same horizontal line. I might be missing something.

7 0

3 years ago

Write what the expressions below best represent within the context of the word problem.

Brilliant_brown [7]

X=2 NICKELS.

3*2=6 QUARTERS.

PROOF:

.25*6+.05*2=1.60

1.50+.10=1.60

1.60=1.60

3 0

3 years ago

. put these numbers in order, from least to greatest. if you get stuck, consider using a number line. 3.5 -1 4.8 -1.5 -0.5 -4.2

luda_lava [24]

-4.2, -3.5,-2.1,-1.5,-1,-0.5,0.5,2,3.5,4.8

7 0

1 year ago

What is the average rate of change from x = −3 to x = −4?

Vika [28.1K]

Answer:

-2

Step-by-step explanation:

Since it would be immensely helpful to know the equation of this parabola, we need to figure it out before we can continue. We have the work form of a positive upwards-opening parabola as

$y=a(x-h)^2+k$

where a is the leading coefficient that determines the steepness of lack thereof of the parabola, x and y are coordinates of a point on the graph, and h and k are the coordinates of the vertex. We know the vertex: V(-3, -3), and it looks like the graph goes through the point P(-2, -1). Now we will fill in the work form equation and solve for a:

$-1=a(-2-(-3))^2-3$

which simplifies a bit to

$-1=a(1)^2-3$

and

-1 = a(1) - 3. Therefore, a = 2 and our parabola is

$y=2(x+3)^2-3$

Now that know the equation, we can find the value of y when x = -3 (which is already given in the vertex) and the value of y when x = -4. Do this by subbing in the values of x one at a time to find y. When x = -3, y = -3 so the coordinate of that point (aka the vertex) is (-3, -3). When x = -4, y = -1 so the coordinate of that point is (-4, -1). The average rate of change between those 2 points is also the slope of the line between those 2 points, so we will use the slope formula to find it:

$m=\frac{-1-(-3)}{-4-(-3)} =\frac{2}{-1}=-2$

And there you have it! I'm very surprised that this question sat unanswered for so very long! I'm sorry I didn't see it earlier!

5 0

2 years ago